Re: [PATCH 1/2] iio: imu: adis16460: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops

[Ardelean, Alexandru]

On Sun, 2019-11-03 at 11:25 +0000, Jonathan Cameron wrote:
> On Wed, 30 Oct 2019 17:33:14 +0800
> zhong jiang <zhongjiang@xxxxxxxxxx> wrote:
> 
> > On 2019/10/30 17:13, Ardelean, Alexandru wrote:
> > > On Wed, 2019-10-30 at 16:19 +0800, zhong jiang wrote:  
> > > > [External]
> > > > 
> > > > It is more clear to use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs
> > > > file
> > > > operation rather than DEFINE_SIMPLE_ATTRIBUTE.  
> > > Not sure if "more clear" is the word.  
> > Should be more clearly. :-)
> > > But it is more correct to use DEFINE_DEBUGFS_ATTRIBUTE(), since they
> > > are
> > > debugfs attrs.
> > > 
> > > In any case, this is no big deal.
> > > So:
> > > 
> > > Reviewed-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> > >  
> > > > Signed-off-by: zhong jiang <zhongjiang@xxxxxxxxxx>
> I started looking into why this attributes were introduced.
> There are potential issues, so Alex can you confirm you've tested this
> series.  Whilst it looks right, it seems some other patches making this
> change have had to switch over to the unsafe registration functions.

I haven't tested this locally yet.
Will try to alloc some time for this.

> 
> https://patchwork.kernel.org/patch/11051725/
> https://lkml.org/lkml/2019/10/30/144
> 
> The reference counting is subtly different between the two versions.
> Seems you are getting some push back on similar patches.
> 
> Perhaps a v2 with reference to the other threads if those get resolved
> to say it is sensible to make this change.
> 
> Thanks,
> 
> Jonathan
> 
> 
> > > > ---
> > > >  drivers/iio/imu/adis16460.c | 6 +++---
> > > >  1 file changed, 3 insertions(+), 3 deletions(-)
> > > > 
> > > > diff --git a/drivers/iio/imu/adis16460.c
> > > > b/drivers/iio/imu/adis16460.c
> > > > index 6aed9e8..2e7a582 100644
> > > > --- a/drivers/iio/imu/adis16460.c
> > > > +++ b/drivers/iio/imu/adis16460.c
> > > > @@ -87,7 +87,7 @@ static int adis16460_show_serial_number(void
> > > > *arg, u64
> > > > *val)
> > > >  
> > > >  	return 0;
> > > >  }
> > > > -DEFINE_SIMPLE_ATTRIBUTE(adis16460_serial_number_fops,
> > > > +DEFINE_DEBUGFS_ATTRIBUTE(adis16460_serial_number_fops,
> > > >  	adis16460_show_serial_number, NULL, "0x%.4llx\n");
> > > >  
> > > >  static int adis16460_show_product_id(void *arg, u64 *val)
> > > > @@ -105,7 +105,7 @@ static int adis16460_show_product_id(void *arg,
> > > > u64
> > > > *val)
> > > >  
> > > >  	return 0;
> > > >  }
> > > > -DEFINE_SIMPLE_ATTRIBUTE(adis16460_product_id_fops,
> > > > +DEFINE_DEBUGFS_ATTRIBUTE(adis16460_product_id_fops,
> > > >  	adis16460_show_product_id, NULL, "%llu\n");
> > > >  
> > > >  static int adis16460_show_flash_count(void *arg, u64 *val)
> > > > @@ -123,7 +123,7 @@ static int adis16460_show_flash_count(void
> > > > *arg, u64
> > > > *val)
> > > >  
> > > >  	return 0;
> > > >  }
> > > > -DEFINE_SIMPLE_ATTRIBUTE(adis16460_flash_count_fops,
> > > > +DEFINE_DEBUGFS_ATTRIBUTE(adis16460_flash_count_fops,
> > > >  	adis16460_show_flash_count, NULL, "%lld\n");
> > > >  
> > > >  static int adis16460_debugfs_init(struct iio_dev *indio_dev)